FinOS

A Local-First AI-Powered Personal Finance Operating System (Built in Rust)

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🚀 Overview

FinOS is a multi-platform, AI-powered personal finance engine built around a modular Rust core.

It enables users to track, analyze, and optimize:

• Daily expenses (UPI, Cash, Cards, Net Banking)
• SIP investments with projected growth simulation
• Recurring subscriptions
• Lending & borrowing records
• Hierarchical spending categories (e.g., Travel → Metro → Flights → Cabs)

Designed as a privacy-first, local-first financial system, FinOS can be accessed via:

• Linux Terminal (CLI)
• Web Interface
• Windows Desktop App
• Android Mobile App

FinOS is not just an expense tracker — it acts as a personal financial intelligence layer.

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🧠 Core Philosophy

• Local-first architecture
• Modular Rust-based core engine
• Self-hostable backend
• Privacy-focused data ownership
• AI-assisted personalization
• Cross-platform accessibility

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🛠 Tech Stack

🧱 Core Engine

• Rust (modular library crate)
• serde (serialization)
• sqlx / rusqlite (database layer)
• chrono, uuid
• argon2 + ring (encryption & key derivation)

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🌐 Backend API

• Axum (REST API layer)
• SQLite (local storage)
• PostgreSQL (optional cloud sync)

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🖥 Desktop Application

• Tauri

  • Rust backend
  • Web-based UI
  • Cross-platform desktop support

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🌍 Web Frontend

• Leptos (Rust-native web UI) OR
• React (optional frontend layer)

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📱 Android Application

• Rust core compiled as shared library
• Kotlin UI via JNI OR
• Flutter + Rust FFI bridge

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🤖 AI Layer

• Rule-based keyword classification (Phase 1)
• Embedding-based semantic categorization (Phase 2)
• User correction learning system
• Optional LLM integration

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🔥 Key Features

💳 Expense Tracking

• Payment mode detection (UPI, Cash, Cards)
• Hierarchical category system
• AI-based sub-category classification
• Monthly & predictive analytics
• Digital vs physical spending ratio

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📈 SIP Investment Engine

• Monthly investment tracking
• Future value projection
• Return rate simulation
• Long-term portfolio estimation

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🔁 Subscription Management

• Recurring billing engine
• Renewal reminders
• Annual cost breakdown
• Subscription waste detection

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💰 Lending & Loan Ledger

• Track money lent or borrowed
• Repayment logging
• Outstanding balance calculation
• Optional interest computation

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📊 Smart Analytics

• Monthly burn rate analysis
• Category drift detection
• Spending pattern intelligence
• Personalized financial insights

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🏗 Architecture Overview

                ┌──────────────┐
                │   Android    │
                └──────┬───────┘
                       │
 Linux CLI ─────────▶  Rust Core Engine  ◀──────── Desktop App
                       │
                ┌──────▼───────┐
                │   Backend    │
                └──────┬───────┘
                       │
                ┌──────▼───────┐
                │   Database   │
                └──────────────┘

The Rust core acts as the shared financial logic layer across all platforms.

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🗄 Database Design (High-Level)

• expenses
• categories (hierarchical tree structure)
• payment_modes
• sips
• subscriptions
• loans
• loan_transactions
• user_category_overrides
• embeddings (optional AI layer)

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🔐 Security

• Encrypted local database
• Password-derived key (Argon2)
• Optional biometric unlock (mobile)
• Self-hostable backend for full data ownership

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📌 Use Cases

• Power users managing detailed personal finances
• Investors tracking SIP growth
• Individuals managing informal lending
• Privacy-focused users avoiding third-party finance apps
• Developers exploring multi-platform Rust architectures

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🌱 Future Roadmap

• AI receipt OCR
• Automated UPI SMS parsing
• CSV import/export
• Multi-currency support
• Net worth dashboard
• P2P sync with CRDTs
• Self-hosted deployment toolkit

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💡 Vision

FinOS aims to become:

A local-first, AI-powered financial operating system — giving users complete control over their money, insights, and data.

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📜 License

MIT (Planned)

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If you’d like, I can also generate:

• A clean folder structure layout
• A CONTRIBUTING.md
• A technical architecture deep-dive document
• Or a more startup-oriented pitch version for GitHub visitors